DE3932918C2 - - Google Patents

Description

The invention relates to a device for driving water vehicles with a cylinder through which ambient water flows drical body, in which a hydrodyna designed as a screw Mixing drive element is arranged on a shaft, wherein the screw is designed as a rotor of an electrical machine and the cylindrical body from a solenoid solenoid is surrounded.

A device of the type mentioned above is known from GB-Z "Marine Propulsion, July / August 1989, page 40".

In the known device is axially proportional short pipe is provided, which is flowed through by ambient water becomes. By means of radial struts is an axial shaft aggregate held centrally, in which a shaft is mounted in a fixed position Sleeve is rotatably mounted. One sits on the rotating shaft Screw, the wings of which at their free ends turn with a tubular component are provided. The tubular component carries a rotor iron ring on its outer circumference and on it again permanent magnets. These permanent magnets are located a small radial distance from a stator that is in the outer Tube of the device is integrated. The outer tube works with it at the same time as a stand protection cylinder.

The screw with the ring-shaped rotor iron and the permanent magnets therefore form the rotor of an electrical machine, whose stator is arranged in the outer tube of the device is. If the stator is now excited by an alternating current,  so the rotor turns, i. H. the screw in the outer tube the device and thus generates a feed.

In principle, the known arrangement has the function of a Alternating current machine, with the result that an alternating current for Excitation of the stator windings is required. With the known An AC generator is provided for this purpose, which is driven by a diesel engine and its Power range from 40 kW to 1500 kW is specified.

The known arrangement is therefore very mechanical and electrical expensive because first the chemical energy of a fossil Fuel (diesel oil) in mechanical energy, then in again electrical energy and finally mechanical Energy that needs to be converted. This creates a poor efficiency, and the arrangement is moreover only suitable for surface vehicles because of a diesel aggregate with reasonable effort only for surface vehicles is operable.

Another device for driving watercraft is from a lecture manuscript by Intichar, L., Erlangen, known as "Superconducting Machines", the occasion of a lecture that was given as part of a seminar "Superconductivity technology" on May 13 and 14, 1985 at school for nuclear technology at the Karlsruhe Nuclear Research Center.

In this known device is on board a surface water schiffes a mechanical drive consisting of two diesel medium speed machines. The diesel machines mechanically drive two superconducting generators which in turn is electrically a superconducting unipolar machine drive. The superconducting unipolar machine in turn drives in a conventional way over a wave a usual ship screw on. Alternatively, it is proposed for  superconducting machine either a unipolar machine from Disc type with homogeneous axially directed magnetic field or a Unipolar machine of the drum type with radially directed magnet field.

In the known device, which is apparently for civilian users areas in surface vessels is intended a major possible advantage of a unipolar machine given away, namely that a unipolar machine in principle only one moving part, namely the moving conductor with the drive element rotatably connected therewith, the again generates the necessary propulsive force. In the known device is rather a complicated arrangement with diesel engines, superconducting generator and superconducting Unipolar machine used, which is not only extremely expensive is, but also periodically due to the large number alternately moving parts, e.g. B. the pistons of the diesel engines, generates significant noise.

The known device is therefore only for the civilian Suitable applications.

Another device for driving watercraft is from the GB-Z "Maritime Defense, The Journal of International Naval Technology ", 12/1988, page 445.

This known device is a so-called magnetohydrodyna mixer drive (MHD drive), in which a medium that contains mobile charge carriers, both electrical and a magnetic field is also impressed. As a result of one acting electrical field, the charge carriers get into Movement, and then it becomes due to the movement of the charge carriers in the magnetic field on the charge carriers the so-called Lorentz force exerted from the cross product of the Magnetic field and velocity vectors in results in a known manner.  

In this known watercraft drive is one of order pipe through which the supply water flows is symmetrical Surrounded tube axis arranged superconducting saddle coils. The saddle coils thus generate a magnetic field, the Direction perpendicular to the pipe axis. There are two in the pipe capacitor-like plate electrodes in the axial direction arranges so that the generated by these plate electrodes magnetic field also perpendicular to the axis direction, however also runs perpendicular to the direction of the magnetic field. This has the consequence that the free charge in the tube carriers of the surrounding water, namely the ions of the salt water, a Lorentz force is communicated in the axial direction of the Rohres runs. The known arrangement thus produces one Recoil force from the axially moving charge carriers in the tube comes from. In the known device for driving a Watercraft becomes a magnetic field strength with the saddle coils of 2 T with a current of 2000 A, resulting in a Recoil force of 8 kN.

In the known device it is advantageous that the drive unit requires no moving elements and therefore practically no drive noise occur. Because of that such arrangements are also suitable for military purposes, especially for driving submarines.

However, the known device has the disadvantage that the efficiency is relatively low, the drive generated force, based on the energy used, therefore unfavorable is.

From DE-PS 8 73 362 is a drive for watercraft known in which the drive by a propeller in one approximately in the vehicle longitudinal direction shaft is effected. The shaft can be in the form of a downstream ver young pipe.  

From DE-PS 8 88 515 a high-speed ship is known, which as Hydrofoil is trained. Are with this speedboat Propeller propeller spaced from the fuselage at the bottom of stilts on which the trunk of the Schnellschiffes when driving fast over the water surface raises.

From CH-PS 4 94 672 is a motor boat with a screw drive known in which the screw in a ver from bow to stern running water guide works in the longitudinal direction of the boat runs.

From DE-Z: HANSA, 1989, No. 9/10, pages 681 to 684 High-performance engines for ship propulsion systems known magnetohydrodynamic drives can also be used. In this context, superconducting is also proposed Use solenoids. In this context, too proposed using newer superconductors for this purpose, the become superconducting already at -200 ° C.

Unipolar machines per se are generally known, e.g. B. from the DE book: Moeller / Fricke / Frohne / Vaske, Basics of Electrical engineering; B. G. Teubner, Stuttgart 1986, pages 187 to 191, in particular Fig. 4.43.

"Solenoid coils" are within the scope of the present application to understand such cylindrical solenoids, which in comparison axially long to the diameter. More details this can be found in the DE book by Schnell, G. "Magnete", Verlag Karl Thiemig, Munich, 1973, page 139ff.

The invention is therefore based on the object of a device of the type mentioned in such a way that with a DC drive with the lowest possible noise the greatest possible propulsive force at low Energy use is achieved.

On the one hand, this object is achieved according to the invention by that the electrical machine is a unipolar machine, at the cylindrical body is designed as a tube, and the Solenoid in the tube a substantially axial Constant magnetic field generated, and that the screw at least comprises a radial electrical conductor, the one hand with a first supply line running in the shaft and on the other hand with a second supply line running along the pipe is electrically connected.

The object is further achieved in that the electrical Machine is a unipolar machine, in which the cylindrical Body is designed as a tube, and the magnetic coil at least in areas an essentially radial constant magnetic field generated, and that the tube at least one essentially electrical running parallel to an axis of the shaft Conductor that passes through the radial area of the magnetic field runs and is connected at both ends to supply lines.

The object on which the invention is based is achieved in this way completely solved. By using a configuration, which are designed exclusively in the manner of a unipolar machine is with only one moving part, namely with the moving conductor and the drive element integrated with it, generates the necessary propulsive force. So it's not Drive elements with periodically alternating linear movements Machine elements required, still complicated structures usual DC drives, such as those in Unter sea boats can be used. The device according to the invention rather has an extremely simple structure and is therefore suitable especially for use in the maritime sector.

The invention also has the essential advantage that the Screw and the electrical conductor in one piece are combined so that the electrical conductors are hydrodynamic  do not appear. Here you make yourself in take advantage of the fact that a screw as a hydrodynamic drive element for receiving electri suitable conductors that run radially or axially can.

As already mentioned, unipolar machines are known per se, for example from the textbook by Pohl "Introduction to Physics ", 20th edition, 1967, volume 2" Elektrizitätslehre ", pages 69 and 101 as well as from the textbook by Flegler, Grundgebiete of electrical engineering, page 219.

In a preferred embodiment of the aforementioned Embodiment of the invention runs through the conductor at least one wing of the screw.

This measure has the advantage of being particularly hydrodynamic Favorable shape arises because the conductor is not a separate one and thus an element with flow resistance in appearance occurs.

In a further preferred embodiment of the first mentioned embodiment are the tube and the screw torsionally rigidly connected.

This measure has the advantage that it is mechanically stable Unity of tube and screw is created.

In the invention it is further preferred if the magnetic coil comprises at least one solenoid coil.

This measure has the advantage that it is particularly simple Coil configuration is used, the hydro as a structural unit is dynamically favorable, which can be easily wound and which can also be handled without problems in the superconducting version is.  

The screw is preferably multi-start and coaxial with Solenoid coil arranged.

This creates a compact, hydrodynamic, inexpensive one and advantageous in their drive properties or with known means optimizable drive unit, both in Surface ships as well as in submarines in varied Installation type can be used.

In a preferred development of this embodiment two solenoid coils are coaxial and axially apart spaced apart, and the conductor extends axially Direction in the space between the solenoid coils.

This measure has the advantage that it is between the solenoid coil radially emerging magnetic field to one double torque leads, and that the field is sufficiently close axial spacing of the two solenoid coils also on one axially short space can be concentrated and there too runs radially with sufficient homogeneity.

To make the necessary electrical connections between the are fixed and the rotatable elements to produce different combinations possible.

In one embodiment of the invention, the tube is over a first sliding contact with a fixed Power source electrically connected.

This measure has the advantage that the tube is continuous circumferential surface, especially on the sliding contacts can fit well.  

In further embodiments of the invention, the shaft the screw and the screw are connected in a torsionally rigid manner, and the shaft is through a second sliding contact with one fixedly arranged voltage source electrically connected.

With these measures, different kinematic Variations for drive arrangements and electrical connections between shaft, screw and tube, relative to the fixed space Frame of reference.

In yet another group of embodiments the screw is rigidly connectable to the solenoid coil and a radially directed electric field is in that of the Solenoid coil enclosed space can be generated.

These measures have the advantage that in certain operating cases of the watercraft switched to a MHD drive that is free of mechanical noise. For this purpose, the screw is locked and by means of the radial directed electric field in cooperation with the axially directed magnetic field to the surrounding water in the area the screw makes a circular movement around the axis of the screw imprinted around. Since the screw has a guide surface, which is set to the axis, becomes the circular orbiting Ambient water deflected in the axial direction and generated on this way a recoil.  

With the measures explained above it is thus possible to provide a watercraft with a drive that is not in the sensitive application works like a unipolar machine, d. H. with a certain, albeit low, noise level, while in sensitive use, for example when creeping of a submarine is switched to the MHD drive.

In the context of the invention it is particularly preferred if a superconducting coil is used as a magnetic coil because the Driving force in both the unipolar drive with rotating Drive element, as with the MHD drive, the driving force depends directly on the magnetic field strength.

It is particularly preferred here if the coil consists of a High temperature superconductor exists.

This measure has the advantage that depending on the jump temperature of the superconductor only relatively simple cooling devices or even no cooling devices are required at all, if a superconducting material is used to wind the coil that is already at the ambient temperature of the water vehicle is in superconducting state.

Further advantages result from the description and the Drawing.

It is understood that the above and the following standing features to be explained not only in each specified combination, but also in other combinations  or can be used alone without the scope of the to leave the present invention.

Embodiments of the invention are in the drawing are shown and are described in more detail in the following description explained. Show it:

Figure 1 is a schematic view of a current-carrying conductor in a magnetic field, for explaining a unipolar drive.

Fig. 2 is a schematic side view of a first embodiment of a device according to the invention;

FIG. 3 shows, on an enlarged scale, a detail from the illustration in FIG. 2, but for a variant of a drive according to the invention with additional operating options as a MHD drive;

Fig. 4 is an illustration similar to Fig. 2, but for yet another embodiment of the invention;

Fig. 5 to 8 schematic front views of watercraft according to the invention with different arrangements of devices.

In Fig. 1, 10 field lines of a magnetic field B are designated. The magnetic field lines 10 run parallel to one another in a predetermined direction.

An electrical conductor 11 is arranged perpendicular to the magnetic field lines 10 and a direct current I flows through it. The electrical conductor 11 is rotatably held in a direction perpendicular to its extension in bearings indicated by 12 .

Since, as mentioned, the conductor 11 is directed perpendicular to the magnetic field lines 10 and through which current flows, it is deflected perpendicular to its extension and perpendicular to the magnetic field lines 10 as a result of the Lorentz force which is set up, so that it undergoes a rotary movement by one Bearing 12 executes defined axis 14 which is directed parallel to the magnetic field lines 10 .

A torque can be removed via the rotary movement of the electrical conductor 11 about the axis 14 and used for drive purposes.

In Fig. 2, 20 designates a drive unit for water vehicles.

A solenoid coil 21 is arranged rotationally symmetrically about an axis 22 . The solenoid coil 21 can be a resistive, ie normally conductive coil, or else a superconducting coil, for which purpose further details are not shown in the figures for the sake of clarity.

The solenoid coil 21 is arranged on an outside of a water vehicle, so that its interior is filled with ambient water.

23 with a space-fixed support of the solenoid coil 21 is indicated on the hull, in order to clarify that the solenoid coil 21 is not rotatable.

With 24 , the field lines of the magnetic field B generated by the solenoid coil 21 are designated. The field lines 24 ver run inside the solenoid coil 21 substantially in the axial direction and are deflected only in the outer space of the solenoid coil 21 in a radial direction, as is known per se.

A shaft 30 extends coaxially with the solenoid coil 21 along the axis 22 . The shaft 30 is rotatably mounted in fixed bearings 31 . It carries a screw 32 , which is a multi-course Archimedean spiral in the illustrated embodiment.

At the right end in FIG. 2, the shaft 30 carries a first slip ring 33 , which is connected to a first electrical line 34 . The first electrical line 34 passes through the shaft 30 in the axial direction. Radial branch lines 35 extend from the first electrical line 34 and extend through the wing of the screw 32 .

The free ends of the wings of the screw 32 are surrounded by a cylindrical tube 36 which is connected in a rotationally rigid manner to the screw 32 and thus also to the shaft 30 .

The pipe 36 is electrically conductive in the axial direction, either by laying electrical lines running axially, as is the case with the first electrical line 34 in the shaft 30 , or by the pipe 36 being partially or entirely conductive.

What is important in the configuration explained above is that the wings of the screw 32 have current flowing through them in the radial direction, while the conduction of the electrical current in the axial direction through the shaft 30 and through the tube 36 can be carried out in a variety of ways.

A second slip ring 37 is located on the tube 36 . With brushes 38 and 39 , an electrical contact to the slip rings 33 and 37 is made. The brushes 38 , 39 are connected to a first voltage source 40 .

As indicated by an arrow 41 , the radial branch lines 35 are traversed by current in this way, and all of them with the polarity shown radially inwards from the outside. On the other hand, since the magnetic field lines 24 in FIG. 2 are directed from right to left, this means, as a comparison with the basic illustration of FIG. 1 shows, that the shaft 30 has a torque in the clockwise direction from the left side of FIG. 2 considered, communicated.

In this way, the screw 32 is rotated and the drive unit 20 develops a recoil.

Fig. 3 shows the right end of a drive unit 20 ', which is very similar to the drive unit 20 shown in FIG. 2; and therefore the same elements are provided with the same reference numerals.

As can be seen from Fig. 3, the tube 36 is provided on its inner cylindrical surface with a first conductive coating 50 , while the shaft 30 'carries a second conductive coating 51 on its outer cylindrical surface. It goes without saying that the tube 36 'or the shaft 30 ' can also be made overall conductive, for example metallic.

A second electrical line 52 extends in the axial direction through the shaft 30 'and is connected on the one hand to the second conductive coating 51 and on the other hand a third slip ring 53 . A third brush 54 is used to make contact with the third slip ring 53 .

A second voltage source 55 is connected between the third brush 54 and the second brush 39 , which in turn is galvanically connected to the first conductive coating 50 .

While the first voltage source 40 is designed such that the highest possible current I (see FIG. 2) flows through the radial stub lines 35 , the second voltage source 55 is designed such that the highest possible voltage between the conductive coatings 50 , 51 generates becomes. In this way, a radially directed electric field is generated, the field lines 65 of which extend in the radial direction between the conductive coatings 50 , 51 .

Using switches 56 , 57 , first voltage source 40 and second voltage source 55 can be switched into their respective circuits.

When the first switch 56 is closed, only a direct current I flows in the manner already explained via the radial stub lines 35 , and the drive unit 20 'operates in the manner of a unipolar machine, as has already been explained with reference to FIG. 2.

Alternatively, you can switch to an MHD drive be tested.

For this purpose, a parking brake 60 is first applied, with which the shaft 30 'locked in place, ie can be connected in a torsionally rigid manner to the solenoid coil 21 . Now the second switch 57 is closed when the first switch 56 is open. There is now a high DC voltage between the conductive coverings 50 , 51 and the electric field E is formed with the field lines 65 .

Since the field lines 24 of the magnetic field B and the field lines 25 of the electric field E are perpendicular to one another, namely in the axial or radial direction, the ions of the surrounding salt water are communicated a Lorentz force, which is circular around the axis 22 is directed. This is indicated at 66 , where it can be seen that the ambient water circulates clockwise, viewed from the left in FIG. 3.

Since the wings of the screw 32 are provided with guide surfaces inclined to the axis 22 , the ambient water on its circular path is simultaneously deflected in the axial direction and thus also generates a recoil to the drive unit 20 '.

In the embodiment shown in FIG. 4, a drive unit 70 has two solenoid coils 71 a, 71 b, which are arranged coaxially to an axis 72 , but axially spaced apart.

The solenoid coils 71 a, 71 b are penetrated by a common shaft 73 , which in turn carries a screw. There is a screw portion 74 a within the solenoid coil 71 a and a further screw portion 74 b within the solenoid coil 71 b.

An electrically conductive connection to the shaft 73 can be established at its two free ends via sliding contacts 75 a, 75 b.

Within the shaft 73 run axial electrical line pieces 76 a and 76 b, each in the region of the solenoid coils 71 a, 71 b. From the axial electrical lines 76 a, 76 b branch radial branch lines 77 a and 77 b branch off, which radially penetrate the wings of the screw sections 74 a, 74 b.

The radial stubs 77 a, 77 extend b then axially into a tube 78, which in turn surrounds the screw portions 74 a, 74 b and the ten 74 a both with and rotationally fixed to Schraubenabschnit, 74 b, as well as with the shaft 73 is connected.

The line sections running axially in the tube 78 are designated by 79 .

The solenoid coils 71 a, 71 b are flowed through in opposite directions by current, so that they generate axially oppositely directed magnetic fields B. With 85 aa the axially directed magnetic field lines of the solenoid coil 71 a and with 85 ba the corresponding opposite axially running magnetic field lines of the solenoid coil 71 b are designated net. Correspondingly, 85 ar and 85 br denote the radially extending magnetic field lines of the solenoid coils 71 a and 71 b, whereby it should be noted that these radially run in the same sense.

In the configuration shown in FIG. 4, a direct current I is fed via the right sliding contact 75 b into the axially extending electrical line 76 b. The current branches out from there into the radial branch lines 77 b and then flows through the axially extending electrical lines 79 along the tube 78 , in order then to re-enter the radial branch lines 77 a, in the axially directed electrical line 76 a within the to collect the left solenoid coil 71 a and then to be removed again via the left sliding contact 75 a.

In the area of the wings of the screw sections 74 a, 74 b, the same effect now arises as has already been described in detail for FIG. 2. With 86 r, the radially extending current I is designated and it is easy to see that the conditions within the solenoid coil 71 a, 71 b are each two times opposite, so that this results in the same direction of rotation for the shaft 73 .

The current I flowing in the axial direction 86 a strikes in the axial space between the solenoid coil 71 a and 71 b on field lines 85 ar or 85 br running at right angles to its direction of flow, so that a force is exerted there in the circumferential direction on the electrical lines 79 . Here too, the configuration is such that the shaft 73 is informed of the same direction of rotation.

In the drive unit 70 of FIG. 4, both the axially directed magnetic field and the radially directed magnetic field are thus used. It is understood that the arrangement of FIG. 4 can be repeated several times in the axial direction with short brine noids.

It goes without saying that, in the case of exemplary embodiments of the invention, such arrangements can also be selected in which only the radially directed field lines are used and, of course, in the arrangement of FIG. 4, those radially directed field lines can also be used which are to the left and right extend the drive unit 70 into the outer space.

The outer jacket surrounding the screw can be completely closed. Likewise, the solenoid coils 71 a and 71 b can be rigidly connected to one another, for example via a common support tube. In particular, superconducting solenoids can be located on a coil carrier within a common cryostat, so that mechanical forces can be safely intercepted between the solenoids.

In Figs. 5 to 8 show different variants are shown as individual drive units or drive units in tandem ship hulls of over- or under underwater vehicles can be accommodated.

In the variant according to FIG. 5, a single drive unit 20 of the type explained in FIG. 2 is integrated in a ship's hull 90 , so that a minimal flow resistance arises.

In the variant according to FIG. 6, a tandem drive unit 20 a, 20 b on brackets 92 a, 92 b is arranged at a distance from a ship's hull 91 .

In the variant according to FIG. 7, there is again a single drive unit 20 according to FIG. 2 at the lower end of a keel 94 of a ship's hull 93 .

Finally, FIG. 8 illustrates the possibility of arranging a tandem drive unit 20 a, 20 b in a ship's hull 95 such that the direction of the drive unit 20 a, 20 b does not run parallel to the direction of travel, but rather is pivoted about an axis 97 perpendicular to the direction of travel can be, as indicated by an arrow 96 . In underwater vehicles it can be maneuvered in the depth direction, while in overwater vehicles levitation of the ship's hull can be achieved with the aim of reducing the hydrodynamic resistance in the manner of hydrofoils.

It goes without saying that the arrangements of FIGS. 5 to 8 can also be used in combination with one another or in exchange of the individual elements, for example in the case of FIG. 7, in that not a single drive unit 20 at the lower end of the keel 64 , but instead rather, a tandem unit 20 a, 20 b according to the type of FIG. 4 is used.

Claims (13)

1. Device for driving watercraft, with a cylindrical body through which ambient water flows, in which a hydro-dynamic drive element designed as a screw ( 32 ; 74 ) is arranged on a shaft ( 30 ; 73 ), the screw ( 32 ; 74 ) being Designed rotor of an electrical machine and the cylindrical body is surrounded by a solenoid solenoid ( 27 ; 71 ), characterized in that the electrical machine is a unipolar machine, in which the cylindrical body is designed as a tube ( 36 ; 78 ), and the Solenoid solenoid ( 27 ; 71 ) in the tube ( 36 ; 78 ) generates a substantially axial constant magnetic field (B), and that the screw ( 32 ; 77 ) comprises at least one radial electrical conductor ( 35 ; 74 ), which is electrically connected on the one hand to a first supply line ( 34 ; 76 ) running in the shaft ( 30 ; 73 ) and on the other hand to a second supply line running along the tube ( 36 ; 78 ) t. 2. Device according to claim 1, characterized in that the conductor ( 35 ; 77 ) extends through at least one wing of the screw ( 32 , 74 ). 3. Apparatus according to claim 1 or 2, characterized in that the tube ( 36 ) and the screw ( 32 ) are rotatably connected miteinan. 4. Apparatus for driving watercraft, with a cylindrical body ( 78 ) through which ambient water flows, in which a hydrodynamic drive element designed as a screw ( 74 ) is arranged on a shaft ( 73 ), the screw ( 74 ) as a rotor of an electrical one Machine designed and the cylindrical body is surrounded by a magnet coil ( 71 ), characterized in that the electrical machine is a unipolar machine, in which the cylindrical body is designed as a tube ( 78 ), and the magnet coil ( 71 ) is at least partially essentially radial constant magnetic field ( 85 ar, 85 br) generated, and the tube ( 78 ) comprises at least one substantially parallel to an axis ( 72 ) of the shaft ( 73 ) extending electrical conductor ( 79 ) through the radial region of the magnetic field ( 85 ar, 85 br) runs and is connected at both ends to supply lines ( 76 ). 5. The device according to one or more of claims 1 to 4, characterized in that the magnetic coil comprises at least one solenoid coil ( 21 ; 71 ). 6. The device according to claim 5, characterized in that two solenoid coils ( 71 a, 71 b) are arranged coaxially and axially spaced apart, and that the conductor ( 79 ) in the axial direction in the gap between the solenoid coils ( 71 a, 71 b) runs. 7. The device or more of claims 1 to 6, characterized in that the tube (36) fixed in space via a first sliding contact (37/39) with an electrically connected to higher-level voltage source (40) for a. 8. The device according to one or more of claims 1 to 7, characterized in that the shaft ( 30 ; 73 ) of the screw ( 32 ; 74 ) and the screw ( 32 ; 74 ) are rotationally rigidly connected to one another, and that the shaft ( 30 ; 73) via a second sliding contact (33/38; 75) having a spatially fixed voltage source (40) is electrically connected. 9. The device according to one or more of claims 1 to 8, characterized in that the screw ( 32 ) rotatably connected to the solenoid coil ( 21 ) and that a radially directed electric field (E) in the solenoid coil ( 21 ) enclosed Space can be generated. 10. The device according to claim 9, characterized in that the electric field (E) between the tube ( 36 ') and the shaft ( 30 ') can be generated. 11. The device according to claim 10, characterized in that the shaft ( 30 '), the screw ( 32 ) and the tube ( 36 ') are rotationally rigidly connected to each other, and that a voltage source ( 55 ) on the one hand with the tube ( 36 ' ) and on the other hand can be connected to the shaft ( 30 ') via sliding contacts ( 37/39 , 53/54 ). 12. The device according to one or more of claims 1 to 11, characterized in that the solenoid coil superconducting coil. 13. The apparatus according to claim 12, characterized in that the coil consists of a high temperature superconductor.